Power quality improvement using self-supported Dynamic Voltage Restorer (DVR) in distribution system

In this paper a new control algorithm for self-supported Dynamic Voltage Restorer (DVR) is analysed. DVR is used to mitigate the power quality problems in terminal voltage like voltage sag, swell, harmonics etc. Here two PI (Proportional Integrator) controllers are used for regulating the DC bus voltage and the load voltage. The focus of this paper is to reduce the active power injected by DVR. Synchronous Rotating Frame (SRF) theory is used to extract the fundamentals of terminal voltage and reference voltage is genereted. The error between sensed load voltage and reference load voltage is used to generate the control signal for the DVR. The compensation of voltage sag, swell, harmonics is evaluated using the Self-supported DVR. The DVR has been modelled using MATLAB software with its Simulink and Sim-power system (SPS) block set tool boxes.